Wind Turbine Payback in Chittenden County, VT
Wind turbine payback in Chittenden County
No. The turbine wears out before it pays for itself.
At 30 m, the height a home turbine tower usually reaches, the wind in Chittenden County, VT averages 3.82 m/s (8.5 mph). A 10 kW turbine there would make about 5,707 kWh a year, worth $1,366 at VT's 23.93¢/kWh. Against an installed cost of about $100,000, that is a payback of 73 years, and the turbine is built to last about 20.
What to do in Chittenden County
A home turbine is not worth buying for savings in Chittenden County unless your spot is far windier than the county average, 6.2 m/s at the hub against 3.82 m/s here. Per kW, solar panels would make about 1,031 kWh a year here against the turbine's 571, so get a solar quote first.
What would have to change
- Power would have to cost 88¢/kWh, 3.7 times what VT pays now.
- Or the average wind at the hub would have to be 6.2 m/s instead of 3.82. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of VT
Chittenden County is the 2,198th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in VT is Franklin County at 3.97 m/s, payback 65 years.
Month by month in Chittenden County
March is the strongest month here, at 4.56 m/s and about 823 kWh. August is the weakest, 3.10 m/s and 248 kWh, so the best month makes 3.3 times the worst. November to March brings in 56% of the year's output in Chittenden County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 4.31 m/s | 701 kWh | $168 |
| February | 4.53 m/s | 732 kWh | $175 |
| March | 4.56 m/s | 823 kWh | $197 |
| April | 4.31 m/s | 679 kWh | $162 |
| May | 3.66 m/s | 423 kWh | $101 |
| June | 3.31 m/s | 298 kWh | $71 |
| July | 3.14 m/s | 257 kWh | $62 |
| August | 3.10 m/s | 248 kWh | $59 |
| September | 3.31 m/s | 298 kWh | $71 |
| October | 3.68 m/s | 433 kWh | $104 |
| November | 3.93 m/s | 511 kWh | $122 |
| December | 4.02 m/s | 567 kWh | $136 |
What a taller tower would buy
Measured at 10 m the wind in Chittenden County averages 2.63 m/s; at 50 m it is 4.54 m/s. That gives a shear exponent of 0.339, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 3,676 to 9,580 kWh a year, 161% more, before counting the extra cost of the taller tower. Why tower height decides it explains the shear behind these numbers.
| Hub height | Average wind | Output | Payback |
|---|---|---|---|
| 20 m | 3.33 m/s | 3,676 kWh | over 100 years |
| 30 m | 3.82 m/s | 5,698 kWh | 73 years |
| 40 m | 4.21 m/s | 7,674 kWh | 55 years |
| 50 m | 4.54 m/s | 9,580 kWh | 44 years |
Counties around Chittenden County
3 of the 6 closest counties are windier at turbine height; the windiest, Clinton County, averages 4.11 m/s.
- Lamoille County, VT: 3.55 m/s, 4,530 kWh, payback 92 years (24 mi)
- Grand Isle County, VT: 3.97 m/s, 6,428 kWh, payback 65 years (26 mi)
- Washington County, VT: 3.55 m/s, 4,530 kWh, payback 92 years (26 mi)
- Franklin County, VT: 3.97 m/s, 6,428 kWh, payback 65 years (28 mi)
- Addison County, VT: 3.43 m/s, 4,056 kWh, payback over 100 years (30 mi)
- Clinton County, NY: 4.11 m/s, 7,143 kWh, payback 48 years (37 mi)
Sun versus wind in Chittenden County
Chittenden County gets 3.53 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,031 kWh a year; one kW of the turbine above makes 571. Kilowatt for kilowatt, panels make 1.8 times as much here as the turbine. Panel output assumes an 80% system performance ratio. Wind or solar runs the same comparison for every county.
How this is worked out
Wind is NASA's Power climate record, the 2001-2025 average at 10 m and 50 m for the county's centre, carried to 30 m with this county's own measured wind shear and spread into hours with a Rayleigh distribution. The turbine is a generic 10 kW, 7 m rotor machine with 10% losses. Cost is $10,000 per kW installed with no tax credit, because the federal one ended in 2025. One county-centre number cannot see your hilltop or your tree line, so treat it as the starting point for a site survey, not a substitute. The full method and its weak spots are in how the numbers are made.